There are different types of natural disasters. For instance there are Tornados, Hurricanes, and Earth Quakes, etc. So i will give you an explanation of how they happen and a video of them happening.

Hurricanes form over the ocean using warm moist air. Hurricanes start out as a tropical depression. Normally Hurricanes form over the warm part of the ocean. Hurricanes use the warm moist air as fuel. Since the warm air rises up it creates an area of lower air pressure below. Air from surrounding areas with higher air pressure will start to push into the lower pressure area and the "new" air becomes warm and moist and rises, too. As the warm air will start to rise like the other warm air the surrounding air swirls in to take its place. Now the warm air that rised starts to cool down and the water in the air forms clouds. Now the the hurrricane moves and gains more power from the warm evaporating air that is coming off the ocean.

Tornados form from warm air coming from the gulf of mexico and cold air coming from canada. When the two air masses collide, it creates an air vortex called a tornado. Tornados cause destruction and in most cases injury and death.

Earth Quakes

Earth Quakes are useually caused when two blocks of the earth suddenly slip past one another. The surface where they slip is called fault plane. The earth has many differetn layers. These layers are called; The inner core, Outer core, Mantle and Crust. They can be refered to as puzzle peices. These puzzle pieces slowly move around, sliding past one another and bumping into each other. We call these puzzle pieces tectonic plates. The plate boundaries are made up of many faults. Since the edges of the plates are rough, they get stuck while the rest of the plate keeps moving. Finally, when the plate has moved far enough, the edges unstick on one of the faults and there is an earthquake.